Japanese Laid-Open Patent Publication No. 2009-61747 discloses a driver apparatus where it is possible to arbitrarily select the number of tone bits for tone data and to speed up processing by carrying out data processing in accordance with such number of tone bits. This driver IC (driver apparatus) is equipped with a shift register unit including a reset function, a latch circuit unit to which tone data is transferred from the shift register unit, an SLCK counter that includes a reset function and counts strobe clock signals, and a tone control circuit unit controlling a light emission time of LED elements in accordance with tone values shown by the tone data based on the count number of the SCLK counter.